用所给词的正确形式填空。

1. It is interesting _________ (know) something about animals.

2. __________ (not open) the door. It is cold outside.

3. She can work out the difficult question _________ (easy)

4. Please keep ___________ (quietly) in the reading - room

5. —Where is my cup?  

   —__________ (you) is over there.

6. What about _________ (go) fishing with us tomorrow?

取一定量的Na₂CO₃和Na₂SO₄混合物溶液与过量盐酸反应，生成2.016L CO₂（标准状况），然后加入足量的Ba（OH）₂溶液，得到沉淀的质量为2.33g．试计算混合物中Na₂CO₃和Na₂SO₄的物质的量分别为多少．